Retractable hydrofoil on vessel

ABSTRACT

Methods, systems, and devices are provided for a vessel comprising a retractable hydrofoil. The vessel can include a hull and one or more hydrofoil assemblies connected to the hull. Each hydrofoil assembly can further include a support structure and a hydrofoil operably connected to the hull via the support structure. Each of the hydrofoil assemblies can be configured to retract or extend from the hull such that the hydrofoil of each of the hydrofoil assemblies can move away or move close to the hull. During operation, one or more of the hydrofoils can be submerged beneath a water line. Alternatively, during a cruising speed of the vessel, one or more of the hydrofoils retracted from being submerged beneath the water line.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/830,981, filed Apr. 8, 2019, which is hereby incorporated byreference in its entirety.

BACKGROUND

A hydrofoil ship is a ship that has lift generating wings, foils, orhydrofoils, under the water's surface. As the ship moves, the foilscreate hydrodynamic lift from the motion of the water over theirsurface. The amount of lift generated is proportional to the plan areaof the foils, the profile of the foils, the angle of attack of thefoils, and the square of the average fluid velocity over the foils.

As the speed of the ship in the water increases, the foils generate anincreasing amount of lift, until eventually the lift force exceeds theweight of the craft. At a certain point, enough lift can be generatedsuch that the lift force is greater or equal to that of the weight ofthe ship. At this point, the craft will accelerate vertically, liftingthe entire hull of the ship out of the water. This state is called beingfoilborne. The speed at which this takes place is called the take-offspeed. A foilborne ship is advantageous because the ship will no longerexperience resistance and friction experience on the hull when the hullitself is buoyant on water.

On the other hand, as the ship continues to increase its speed, the liftcreated by the foils also increases as a function of the square of theship's velocity. If this lift force is in excess of the weight of thecraft, a vertical acceleration will occur. If the lift force continuesto be greater than the weight of the ship, the ship will keep risinghigher out of the water until the foils have breached the surface of thewater. This is called foil ventilation. At this point, the lift forcewill collapse, and the ship can uncontrollably descend back to thewater's surface. The maximum speed that the craft can travel at beforethe foils begin to ventilate due to breeching the water's surface iscalled the cruise speed.

Currently, vessels equipped with hydrofoils have a static hydrofoilassembly. The hydrofoil assembly include hydrofoils that are fixed ontothe ship such that the distance from the hydrofoil to the position ofany point of the hull is always constant. With a static foil assembly,there is little to no difference between the takeoff speed, the speed(depending on the configuration of the hydrofoil) to bring enough liftthe vessel foilborne, and the cruise speed. Because of the fixedpositioning and configuration of the foil, the foil will always have aconstant plan area, profile, shape, and angle of attack to the waterline.

This means that the only variable that will affect the amount of liftgenerated will be the vessel's speed. In these cases of current vesselswith hydrofoils, there can only be one point, or one speed, where thelift generated is equal to the weight of the vessel.

At any slower speeds, the vessel either cannot be foilborne or willdescend from being foilborne, which defeats the primary purpose of ahydrofoil. At any higher speeds, the vessel, while foilborne, willcontinue to rise vertically until the vessel reaches a state of foilventilation.

Thus, current vessels that utilize hydrofoils neither considers thedifference between cruise speed and takeoff speed nor achieve havingboth a takeoff speed and a different, primarily faster, cruise speed.

BRIEF SUMMARY

The present disclosure relates generally to systems and methods for avessel.

In one aspect, a method, system, or device can include a vesselcomprising a retractable hydrofoil. The vessel can include a hull andone or more hydrofoil assemblies connected to the hull. Each hydrofoilassembly can further include a support structure and a hydrofoiloperably connected to the hull via the support structure. Each of thehydrofoil assemblies can be configured to retract or extend from thehull such that the hydrofoil of each of the hydrofoil assemblies canmove away or move close to the hull. During operation, one or more ofthe hydrofoils are submerged beneath a water line. Alternatively, duringa cruising speed of the vessel, one or more of the hydrofoils can beretracted from being submerged beneath the water line.

In one aspect, the support structure of each of the one or morehydrofoil assemblies can include of a pair of elongated booms. In oneaspect, the hydrofoil can further include a leading edge, a trailingedge, and side portions on opposite ends of the hydrofoil such that thepair of elongated booms can be operably connected to the opposite endsof the side portions of the hydrofoil. In one aspect, at least a firsthydrofoil can be submerged beneath a water line when the water vessel isoperational at a given speed. In one aspect, at least a second hydrofoilcan be retracted to a position close to that of the hull such that whenthe ship is operational at a cruising speed, the at least secondhydrofoil can be above the water line and the at least first hydrofoilcan be submerged beneath the water line. In one aspect, the positioningof each hydrofoil of the one or more hydrofoil assemblies can beconfigured to reduce a submerged plan area and maximize a lift to dragratio of the at least the first hydrofoil when operational. In oneaspect, each hydrofoil of the one or more hydrofoil assembles can beconfigured to optimize a stability, balance, and trip of the watervessel. In one aspect, the positioning of each hydrofoil of the one ormore hydrofoil assemblies can be based on at least a velocity of thewater vessel, a lift caused by the one or more hydrofoil assembliesduring operation of the water vessel, a turbulence experienced by thewater vessel during operation of the water vessel, or a combinationthereof.

In one aspect, a ship can include a hull, and a plurality of hydrofoilsoperably connected to the ship, each of the plurality of hydrofoilshaving a plan area, the hydrofoils configured to extend or retract to adistance relative to the position of the hull such that at least a firsthydrofoil of the plurality of hydrofoils can be submerged under waterwhen the ship is operational at a given speed.

In one aspect, the plurality of hydrofoils can be operably connected thehull, connected to a structure supported by the hull, or a combinationthereof. In one example, at least a second hydrofoil of the plurality ofhydrofoils can be retracted to a position close to that of the hull suchthat when the ship is operational at a cruising speed, the secondhydrofoil can be above a water line. In one aspect, the positioning ofeach hydrofoil of the plurality of hydrofoils can be configured toreduce a submerged plan area and maximize a lift to drag ratio of one ormore of the plurality of hydrofoils when operational.

In one aspect, a hydrofoil system can include a foil having a leadingedge, a trailing edge, and two side portions, and can include a firstsupport structure operably connected to one side of the two sideportions of the foil, and a second support structure operably connectedto another side of the two side portions of the foil such that the firstsupport structure and second support structure are operably connected toa vessel.

In one aspect, the width of the beam can be substantially equal to thespan of the foil. In one aspect, the first and second support structurescan be connected to the vessel at each of opposite sides of the vessel.In one aspect, the foil, along with the first support structure andsecond support structure can operably extend and retract verticallyrelative to the position of the vessel along an axis substantiallyperpendicular to that of the axis of a water line.

In one aspect, a hydrofoil can include a thin, u-shaped, structureincluding a base portion that can be substantially flat along a firsthorizontal axis, and two side portions operably connected to opposingedges of the base portion, each of the two side portions havingelongated and substantially flat surfaces suspended perpendicular to theopposing edges of the base portion.

In one aspect, the base portion can include two surfaces that are curvedalong a second horizontal axis. In one aspect, each of the two sideportions are operably connected to a vessel. And in one aspect, the twoside portions can be configured to extend or retract from the vesselsuch that the base portion can move away or move close to a bottomsurface of the vessel.

Other embodiments are directed to systems and computer readable mediaassociated with methods described herein.

A better understanding of the nature and advantages of embodiments ofthe present invention may be gained with reference to the followingdetailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Illustrative embodiments are described with reference to the followingfigures.

FIG. 1A shows a diagram illustrating one embodiment of a vesselaccording to some embodiments of the invention.

FIG. 1B shows an additional diagram illustrating an alternative view ofthe embodiment of the vessel according to FIG. 1A.

FIG. 1C shows a diagram illustrating another embodiment of a vesselaccording to some embodiments of the invention.

FIG. 1D shows an additional diagram illustrating an alternative view ofthe embodiment of the vessel according to FIG. 1C.

FIG. 1E shows a diagram illustrating another embodiment of a vesselaccording to some embodiments of the invention.

FIG. 1F shows an additional diagram illustrating an alternative view ofthe embodiment of the vessel according to FIG. 1E.

FIG. 1G shows a diagram illustrating another embodiment of a vesselaccording to some embodiments of the invention.

FIG. 1H shows an additional diagram illustrating an alternative view ofthe embodiment of the vessel according to FIG. 1G.

FIG. 1I shows a diagram illustrating another embodiment of a vesselaccording to some embodiments of the invention.

FIG. 1J shows an additional diagram illustrating an alternative view ofthe embodiment of the vessel according to FIG. 1I.

DETAILED DESCRIPTION I. Introduction

According to certain embodiments, methods and systems disclosed hereinrelate to a vessel and the operation of a vessel.

The challenge of designing a hydrofoil craft is to do so such that ithas a low takeoff speed, and a high cruise speed. A low takeoff speed isdesirable as it reduces the total power requirement of the engines thatare needed to get to the low drag state this is being foilborne. A highcruise speed is desirable as it allows for faster transit between originand destination. As discussed earlier, because current vessels utilizinghydrofoils have a static hydrofoil assembly, lift generated is only afunction of speed. The amount of lift generated onto a vessel can onlybe achieved by a singular speed. Any higher speed and the lift willcontinue exceed the weight of the ship even when the vessel is alreadyfoilborne and any lower speed will cause the vessel to drop back intothe water. Thus, the takeoff speed and the cruising speed are the sameand can only be one speed.

This configuration is not optimal, especially for commercial vesselstravelling long distances through water. As discussed earlier, once thecommercial vessels, equipped with hydrofoils, becomes foilborne, thespeed at which the commercial vessel became foilborne is alsoessentially the maximum speed of the ship.

Attempts have been made to create a speed envelope between takeoff andcruise speed by changing the lift experienced by the vessel unrelated tothat of speed. However, current attempts come with significantdrawbacks.

Existing methods to increase the envelope of speeds between takeoffspeed and cruise speed include varying one of the three parameters ofthe foil that are not related to speed; plan area, profile of the foilor wing, and angle of attack. Plan area can be reduced by having a foildesign that reduces the plan area as speed increases, includingincorporating a dihedral angle in the foil, and having the tips of thefoil penetrate the water's surface as speed increases. These designshowever have considerable drawbacks such as susceptibility toventilation. The angle of attack can be modified by directly modifyingthe angle of attack of the foil directly, or by altering the pitch ofthe entire craft, or both. The profile of the foils can be altered usingthe addition of flaps (similar to that of ailerons of airplanes) andother lift modifiers that can vary the wings co-efficient of lift. Sincelift is proportional to the square of velocity, any increase of speedresults in a considerable increase in lift. Subsequently, in order toprovide a functional speed range such that lift can be variedindependent of speed, a large and complicated mechanical modification tothe foils is required.

Further, even if the existing methods of changing plan area byincreasing or decreasing the plan area of the submerged foil, changingthe profile of the foil, and/or changing the angle of attack bymodifying the orientation of the foil, the lift to drag ratio is notoptimized. An important consideration when designing a hydrofoil is theminimization of drag, as it is the primary driver of fuel consumption.The amount of drag that the foil produces is very similar to the amountof lift that the foil creates, and is proportional to the plan area,foil profile, angle of attack and average fluid velocity. Therelationship between lift, drag, and angle of attack varies in such away that the lift to drag ratio is maximized at specific angles ofattack. It is desirable to operate the foils at or close to this optimumangle of attack to facilitate the maximum lift to drag ratio.

Further, current hydrofoil vessel's having fixed hydrofoils willexperience even worse drag than vessels that do not utilize hydrofoilsat low speeds. At low speeds, takeoff is not possible, so that thevessels including a fixed position hydrofoil would only add to the crosssectional drag to the vessel as compared to the same vessel without thehydrofoil.

The following specification describes a vessel configured to operateover a large range of speeds while maintaining an optimized lift to dragratio.

II. Exemplary Hydrofoil Vessel

In this specification, reference is made in detail to specificembodiments of the invention. Some of the embodiments or their aspectsare illustrated in the figures. For clarity in explanation, the systemhas been described with reference to specific embodiments, however itshould be understood that the system is not limited to the describedembodiments. On the contrary, the system covers alternatives,modifications, and equivalents as may be included within its scope asdefined by any patent claims. The following embodiments of the systemare set forth without any loss of generality to, and without imposinglimitations on, the claimed method. In the following description,specific details are set forth in order to provide a thoroughunderstanding of the present method. The present method may be practicedwithout some or all of these specific details. In addition, well knownfeatures may not have been described in detail to avoid unnecessarilyobscuring the system.

In addition, it should be understood that steps of the exemplary systemand method set forth in this exemplary patent can be performed indifferent orders than the order presented in this specification.Furthermore, some steps of the exemplary system and method may beperformed in parallel rather than being performed sequentially.

The following specification describes a system including a vesseltravelling on water configured to reach a wide range of operationalspeeds while maintaining an optimized lift to drag ratio.

A. Vessel with Hydrofoil Assembly

In one example, a vessel with a hydrofoil assembly is provided such thatthe hydrofoil assembly allows an optimum lift to drag ratio over a widerange of operational speeds. Specifically, the vessel is configured tooperate a wide range of foilborne speeds while achieving an optimal liftto drag ratio. In this example, a vessel, or ship is equipped with ahydrofoil assembly that, when operated at certain speeds, can createlift to the vessel and bring the vessel foilborne. Once the vessel isfoilborne, the amount of resistance and drag exerted onto the vessel isgreatly reduced and the vessel can travel across water more efficiently.

In one example, the vessel can propel in the water by utilizing motorswith propellers. The motor can be mounted, for example, on the vesselsuch that the propellers on the motors are submerged beneath the waterline whether the vessel is foilborne or not foilborne. In anotherexample, gas turbines can generate thrust and move the vessel with orwithout being foilborne. In another example, a gas turbine or internalcombustion engine generates electric power to electric motors withpropellers. The electric motors can be submerged under the water linewhen the vessel is operational. In another example, a water jet having ajet nozzle operably connected to the vessel can propel the vessel. Inanother example, the hydrofoil assembly includes a motor system, forexample, powered by an internal combustion engine, with propellerseither operably connected to or part of the hydrofoil assembly.

Further in this example, the hydrofoil assembly is also extendable andretractable such that lift can be varied depending on the speed. In thiscase, the hydrofoil assembly can be configured to maximize lift toachieve a low takeoff speed. The hydrofoil assembly can also beconfigured to produce the exact amount of lift required, as to maximizethe moving speed, or cruising speed. Further, the hydrofoil assembly canalso be configured to optimize stability, balance, and trip of thevessel.

In this example, the maximum speed is accomplished by removing portionsof the hydrofoil assembly itself from being submerged under water sothat a higher speed can be reached and still achieve the same amount oflift, with the remaining submerged foils operating at close to or attheir optimum lift to drag ratio.

In one example, a hydrofoil ship has one or more retractable andextendable hydrofoils. The total amount of lift can be decreased withthe increase of speed by physically retracting one or more of the offoils out of the water as the craft increases its speed. This will causethe plan area to decrease by amount equal to the plan area of each ofthe hydrofoils retracted from the water (for example, decrease by 50% iftwo retractable hydrofoils of a total of four equally sized hydrofoilsare retracted from being submerged underwater. The foils that remain inthe water can remain at or close to their optimum angle of attack tominimize drag. Once retracted, the foils will be secured to the hull ina manner that minimizes air drag. In one example, the retractable andextendable hydrofoils can be retracted and extended via a mechanicalsystem connected to the hydrofoil ship. In one example, the mechanicalsystem can be a hydraulic system, including a hydraulic system usinghydraulic actuators. In another example, the mechanical system can be asystem that includes motors and gears.

FIG. 1A illustrates an exemplary floating body or ship with retractablehydrofoils in accordance to one example of the invention. FIG. 1Billustrates the same exemplary ship of FIG. 1A in a different view. Asillustrated in FIGS. 1A-1B, an example floating device 10, or a ship isprovided. In this example, the floating device 10 includes a vessel 100having a hull 110 is resting on a water line 115 where a portion of thevessel 100, including the hull 110, is submerged beneath the water linesuch that the vessel 100 is floating on water. The vessel 100 alsoincludes a hydrofoil assembly 120 operably connected to the vesseleither at the hull 110 or a structure attached to the hull 110. In oneexample, the vessel 100 is a commercial vessel containing a plurality ofshipping containers 102. The vessel 100 illustrated in FIG. 1A-1B isillustrative only. The vessel can be that of any kind of ship such as acommercial ship, commercial vessel, freight ship, military ship, raceboat, surfboard, monohulled ships, catamarans, etc. As illustrated inthe side view of FIG. 1A, the vessel 100 includes four hydrofoilassembly 120's. In another example, there can be any number of hydrofoilassembly 120's on the vessel 100 depending on the size, shape, etc. ofthe vessel 100. In this example, the each of the four hydrofoil assembly120 are spaced evenly across the centerline of the vessel 100. Thisconfiguration allows for an even distribution of lift exerted onto themass of the hull causing an even lift when the vessel 100 isoperational.

In one example, the vessel 100 as illustrated in FIG. 1A-1B is in aresting position. Each of the hydrofoil assembly 120 are fully retractedand each of the hydrofoil assembly 120 is barely submerged underwater.In another example, the vessel 100 is operation such that a propellerconnected to an engine or any kind of kinetic movement device is causingthe vessel to move across the water. In this example, the vessel 100 canbe operating at a speed slow enough that foiling does not need to occurand therefore, the hydrofoil assembly 120 is in a fully retractedconfiguration.

In one example as illustrated in FIGS. 1A-1B, each of the hydrofoilassembly 120 includes a hydrofoil 122 and a hydrofoil support 124. Thehydrofoil 122 of the hydrofoil assembly 120 can cause lift when thevessel 100 is operational and water flows over the surface of thehydrofoil 122. The hydrofoil support 124 connects the hydrofoil 122 tothe vessel 100 either at the hull 110 or another structure operablyconnected to the vessel 100.

1. Foil

In one example, the hydrofoil can include a leading edge or nose, atrailing edge with the profile or shape of a typical wing of an aeroplane. In this example configuration, a top surface of the foil iscurved, and the bottom surface of the foil is also curved such that whenfluid flows above and beneath the foil, a pressure imbalance from themovement of the foil causes a net lift to the foil. This particularconfiguration should be construed as illustrative only. In anotherexample, at least one of the surfaces of the foil can be flat, orconcave. For example, like that of a typical aero plane wing, onesurface, e. g. a bottom surface of the aero plane wing will be flat orsubstantially flat, and one surface, e. g. a top surface of the aeroplane wing will be curved in a concave shape. Other foil shapes, from across-sectional view, can include but not limited to straight shapes,tapered shapes, concave shapes, crescent shapes, etc.

In one example, the foil can pivot about an axis such that the angle ofattack of the foil can be changed where in some instances, movement ofthe foil through water will cause no lift depending on a certainconfiguration of the foil and movement of the foil through water willcause lift depending on another configuration of the foil and so forth.

In one example, the hydrofoil 122 can include a winglet or ailerons orflaps at the trailing edge of the hydrofoil 122. The flaps can changethe overall profile of the foil as well as the angle of attack on thewater and therefore changing lift.

2. Foil and Support Structure

In one example, the hydrofoils 122 are operably connected to the vessel100, either at the hull 110 of the vessel 100 or a different portion ofthe vessel by one or more structures. The hydrofoil 122 is connected tothe hull 110 by a hydrofoil support 124. In one example, the hydrofoilsupport 124 can include a pair of support structure. The pair of supportstructures can be two elongated booms or struts that are substantiallystraight disposed at opposite ends of the hydrofoil 122 configuredvertically and connected to the hull. The two elongated booms of thehydrofoil support 124 can move up and down as to extend and retract fromthe vessel.

In one example, the support structures extend from each of two sideportions of the hull beneath the vessel and connects to a single foilstructure at each of two side portions of the foil. In another example(not shown), a single support structure can extend along a centerline ofthe hull, center portion relative to the beam or center portion from afront-view of the vessel and extend beneath the hull and connect thefoil at a center portion of the foil, also from a front view.

In one example, the support structures are also thin like that of thehydrofoil 122. In one example, the hydrofoil assembly 120 is a u-shapedstructure including a base portion that is substantially flat along afirst horizontal axis. In this example, the first horizontal axis can bethe axis parallel to that of a beam of the vessel 100. The u-shapedstructure can also include two side portions operably connected toopposing edges of the base portion, each of the two side portions havingelongated and substantially flat surfaces similar to that of the baseportion. The two side portions are suspended perpendicular to theopposing edges of the base portion, thus creating a u-shape. In oneexample, the base portion is curved along a second horizontal axis, suchthat the curvature creates lift when the base portion flows throughwater at a certain angle of attack. The second horizontal axis can bethe axis parallel to that of the centerline axis of the vessel 100. Theu-shaped structure is configured to be operably connected to the vesselsuch that the base acts as a hydrofoil and the entire u-shaped structurecan be variably suspended vertically beneath the hull of the ship andretracted vertically to the hull of the ship.

In one example, the span of the hydrofoil 122 is substantially the sameas the width of the beam of the vessel 100.

In another example, not all of the hydrofoils 122 necessarily need to beof the same shape, profile, orientation, or size. Multiple foilingmechanisms can be configured such that some of the hydrofoil assemblies120 are used for foiling and creating the substantive amount of lift andsome of the hydrofoil assemblies 120 are configured for stabilizing thevessel 100 when foilborne.

B. Operation

As illustrated in FIGS. 1C-1D, the vessel 100 includes a plurality ofretractable and extendable hydrofoil assemblies 120. When extended, thehydrofoil 122 of each of the hydrofoil assemblies 120 are submergedbeneath the water line and are a certain distance from a bottom surfaceof the hull 110 of the vessel 100. In this extended configuration, whereeach of the plurality of hydrofoil assemblies are extended, each of thehydrofoil 122 can cause lift to the vessel 100 when the vessel 100 isoperational. As discussed earlier, at some point the speed will createenough lift such that vessel will be foilborne, known as the takeoffspeed. Once the vessel 100 is foilborne, going in the direction oftravel 200, the water drag experienced by the vessel 100 is only due toportions of the hydrofoil assembly 120's including all of the hydrofoils122 and portions of the hydrofoil supports 124.

In the example illustrated by FIGS. 1C-1D, there are four hydrofoilassemblies 120 and each of the hydrofoil assemblies 120 are extended andthe hydrofoils 122 are fully submerged into the water. In one example,the lowest takeoff speed necessary to create lift and cause the vessel100 to be foilborne is achieved with all four hydrofoil assemblies 120fully submerged.

C. Operation at High Speeds

Once the vessel 100 is fully foilborne in the configuration of thehydrofoil assemblies 120 illustrated in FIGS. 1C-1D, any increase inspeed will cause more lift which will eventually cause a problem oncethe lift raises the vessel 100 so much that the hydrofoil 122 reachesthe water line 115.

In one example, as illustrated in FIGS. 1E-1F, once the vessel 100 isfoilborne, the vessel 100 can operate at a higher speed with a reducedplan area of the hydrofoil, such that the lift stays the same (the liftbeing the same as the weight of the vessel) as that of the exampleconfiguration in FIGS. 1C-1D. As illustrated in FIGS. 1E-1F, the twocenter retracted hydrofoil assemblies 120 will cause at least the planarea of the total plan area of the hydrofoils 122 to decrease (forexample by 50% because two of the four totally submerged hydrofoils 122have been retracted fully from the water). However, to maintain the sameamount of lift, the vessel 100 can increase its speed at the directionof travel 300 such that the lift generated by the two outer submergedhydrofoil assemblies 120 will increase, and the total lift experiencedby the vessel will continue to remain the same as when the vessel 100was first foilborne, equal to the weight of the vessel. The result willbe that a new faster speed will be experienced by the vessel 100 in thesame foilborne state. The speed is the new cruising speed.

Additionally, the lift to drag ratio in the configuration illustrated inFIGS. 1E-1F, where one or more hydrofoil assemblies 120 are fullysubmerged and one or more hydrofoil assemblies 120 are fully retracted,are optimized. In this example, instead of changing the angle of attackor profile of each of the submerged hydrofoils 122, 50% of the submergedhydrofoil assemblies 120 are removed. Thus, substantially 50% of thewater drag experienced by the totality of the submerged hydrofoilassemblies 120 is also removed, thereby optimizing lift to drag ratioand optimizing efficiency and power required to move the vessel 100 atthe cruising speed.

In one example, in order to minimize the sudden impact of an entire ¼ or½ of the total amount of plan area, that is the number of foils of thetotal foils removed from the water, the hydrofoils can also beconfigured to change angle of attack by pivoting about its own axis,change plan area, or change profile with ailerons, or a combinationthereof so that the vessel 100 will not experience sudden turbulencewhen the vessel 100 experience a sudden lack of lift when one or morehydrofoil assemblies 120 are retracted from the water line 115.

Since the retraction of an entire hydrofoil from the water wouldnormally produce an abrupt and significant change in lift, the liftgenerated by each of the foils on the craft will be able to be modifiedby configuring a change of angle of attack by pivoting about its ownaxis, plan area, or profile with ailerons, or a combination thereof.This will facilitate the smooth removal of a foil from the water withouthaving an abrupt impact on the total lift generated.

D. Variable Configuration of the Hydrofoil Assembly

FIGS. 1G-1J illustrates substantially the same concepts as that of FIGS.1C-1F, respectively with a slight variation. In the examples illustratedin FIGS. 1G-1J, the hydrofoil supports 124 of the hydrofoil assemblies120 can extend and retract to any length within the minimum retractablelength and maximum extended length. For example, as illustrated in FIGS.1G-1H, the four example hydrofoil assemblies 120 are only partiallyextended as compared to that of previous examples. In this example, thevessel 100 can still achieve lift and become foilborne even without asmuch vertical climb as that of vessels described in previous examples.In this example, the water may be non-turbulent, or laminar, such thatwave profiles are shallow, and a minimal lift can cause the entirevessel to hover above all of the waves of the water that the vessel 100is currently moving across. This is advantageous because the vessel 100will experience even less water drag that of a vessel with fullysubmerged hydrofoil assemblies 120 since at least a portion of thehydrofoil supports 124 will be above the water line 115 as compared tothat of hydrofoil assemblies 120 with hydrofoil supports 124 fullyextended beneath the water line 115.

As illustrated in FIGS. 1I-1J, the same concept applies to thetransition of the vessel 100 from takeoff speed to cruising speed. Inthis example, the one or more hydrofoil assemblies 120 that are keptextended experience less drag than that of hydrofoil assemblies 120fully extended since at least a portion of the hydrofoil supports willbe retracted and above the water line as compared to that of hydrofoilassemblies 120 with hydrofoil supports 124 fully extended beneath thewater line 115. The one or more fully retracted hydrofoil assemblies 120will still be fully retracted and above the water line 115.

In this specification, reference is made in detail to specificembodiments of the invention. Some of the embodiments or their aspectsare illustrated in the drawings.

For clarity in explanation, the invention has been described withreference to specific embodiments, however it should be understood thatthe invention is not limited to the described embodiments. The inventioncovers alternatives, modifications, and equivalents as may be includedwithin its scope as defined by any patent claims. The followingembodiments of the invention are set forth without any loss ofgenerality to, and without imposing limitations on, the claimedinvention. In the following description, specific details are set forthin order to provide a thorough understanding of the present invention.The present invention may be practiced without some or all of thesespecific details. In addition, well known features may not have beendescribed in detail to avoid unnecessarily obscuring the invention.

In addition, it should be understood that steps of the exemplary methodsset forth in this exemplary patent can be performed in different ordersthan the order presented in this specification. Furthermore, some stepsof the exemplary methods may be performed in parallel rather than beingperformed sequentially. The present invention may be practiced withdifferent combinations of the features in each described configuration.

The terminology used herein is for the purpose of describing particularaspects only and is not intended to be limiting of the disclosure. Asused herein, the singular forms “a,” “an,” and “the” are intended tocomprise the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

While the invention has been particularly shown and described withreference to specific embodiments thereof, it should be understood thatchanges in the form and details of the disclosed embodiments may be madewithout departing from the scope of the invention. Although variousadvantages, aspects, and objects of the present invention have beendiscussed herein with reference to various embodiments, it will beunderstood that the scope of the invention should not be limited byreference to such advantages, aspects, and objects. Rather, the scope ofthe invention should be determined with reference to patent claims.

1. A water vessel comprising: a hull; and one or more hydrofoilassemblies connected to the hull, each hydrofoil assembly comprising: asupport structure; and a hydrofoil operably connected to the hull viathe support structure, wherein each of the hydrofoil assemblies areconfigured to retract or extend from the hull such that the hydrofoil ofeach of the hydrofoil assemblies can move away or move close to thehull.
 2. The water vessel of claim 1, wherein the support structure ofeach of the one or more hydrofoil assemblies is comprised of a pair ofelongated booms.
 3. The water vessel of claim 1, wherein the hydrofoilfurther comprises a leading edge, a trailing edge, and side portions onopposite ends of the hydrofoil such that the pair of elongated booms areoperably connected to the opposite ends of the side portions of thehydrofoil.
 4. The water vessel of claim 1, wherein at least a firsthydrofoil is submerged beneath a water line when the water vessel isoperational at a given speed.
 5. The water vessel of claim 1, wherein atleast a second hydrofoil can be retracted to a position close to that ofthe hull such that when the ship is operational at a cruising speed, theat least second hydrofoil is above the water line and the at least firsthydrofoil is submerged beneath the water line.
 6. The water vessel ofclaim 1, wherein the positioning of each hydrofoil of the one or morehydrofoil assemblies is configured to reduce a submerged plan area andmaximize a lift to drag ratio of the at least the first hydrofoil whenoperational.
 7. The water vessel of claim 1, wherein each hydrofoil ofthe one or more hydrofoil assembles is configured to optimize astability, balance, and trip of the water vessel.
 8. The water vessel ofclaim 1, wherein the positioning of each hydrofoil of the one or morehydrofoil assemblies is based on at least a velocity of the watervessel, a lift caused by the one or more hydrofoil assemblies duringoperation of the water vessel, a turbulence experienced by the watervessel during operation of the water vessel, or a combination thereof.9. A ship comprising: a hull; and a plurality of hydrofoils operablyconnected to the ship, each of the plurality of hydrofoils having a planarea, the hydrofoils configured to extend or retract to a distancerelative to the position of the hull such that at least a firsthydrofoil of the plurality of hydrofoils can be submerged under waterwhen the ship is operational at a given speed.
 10. The ship of claim 9,wherein the plurality of hydrofoils are operably connected the hull,connected to a structure supported by the hull, or a combinationthereof.
 11. The ship of claim 9, wherein at least a second hydrofoil ofthe plurality of hydrofoils can be retracted to a position close to thatof the hull such that when the ship is operational at a cruising speed,the second hydrofoil is above a water line.
 12. The ship of claim 9,wherein the positioning of each hydrofoil of the plurality of hydrofoilsis configured to reduce a submerged plan area and maximize a lift todrag ratio of one or more of the plurality of hydrofoils whenoperational.
 13. A hydrofoil system comprising: a foil comprising; aleading edge; a trailing edge; and two side portions; a first supportstructure operably connected to one side of the two side portions of thefoil; and a second support structure operably connected to another sideof the two side portions of the foil such that the first supportstructure and second support structure are operably connected to avessel.
 14. The hydrofoil system of claim 13, wherein the width of thebeam is substantially equal to the span of the foil.
 15. The hydrofoilsystem of claim 13, wherein the first and second support structures areconnected to the vessel at each of opposite sides of the vessel.
 16. Thehydrofoil system of claim 13, wherein the foil, along with the firstsupport structure and second support structure can operably extend andretract vertically relative to the position of the vessel along an axissubstantially perpendicular to that of the axis of a water line.
 17. Ahydrofoil comprising: a thin, u-shaped, structure comprising: a baseportion that is substantially flat along a first horizontal axis; andtwo side portions operably connected to opposing edges of the baseportion, each of the two side portions having elongated andsubstantially flat surfaces suspended perpendicular to the opposingedges of the base portion.
 18. The hydrofoil of claim 17, wherein thebase portion comprises two surfaces that are curved along a secondhorizontal axis.
 19. The hydrofoil of claim 17, wherein the each of thetwo side portions are operably connected to a vessel.
 20. The hydrofoilof claim 17, wherein the two side portions are configured to extend orretract from the vessel such that the base portion can move away or moveclose to a bottom surface of the vessel.